1. Technical Field
The present invention relates to electrosurgical generators and, more particularly, to electrosurgical generators having specific utility in arthroscopic surgical procedures.
2. Discussion of the Prior Art
My aforementioned U.S. patent application Ser. No. 06/447,808 describes an electrosurgical generator which is advantageously useful for arthroscopic surgical procedures at human joints having higher impedance than the 500 Ohms or less of other human tissue sites at which electrosurgical generators have been conventionally employed. Specifically, I describe in that patent application an electrosurgical generator having an output impedance of 1,000 Ohms or greater in order to more closely match the impedance of the human joint. I further describe the problem presented by improper matching of the generator impedance to the human joint at the surgical site, namely: the generator does not efficiently transfer energy to the site, thereby requiring higher power settings at the generator. These higher power settings result in tissue damage, such as necrosis, in the surrounding tissue. My aforesaid patent application further indicates that a generator impedance of 1,000 Ohms or more should be provided to more properly match the impedance of the human joint.
I have now found that the impedance at human joints at which electrosurgery can be employed may vary over a considerably wider range than described in my aforesaid patent application.